The present invention broadly relates to squares, protractors and other geometric layout instruments and tools. Specifically, the present invention is a Multifunction Layout Tool which is capable of performing the functions of an adjustable square, adjustable T-square, a try square, a combination square, a protractor, an angle duplicator, a depth gauge, a rip gauge, a rafter-stair layout tool, and a compass. Art pertinent to the subject matter of the present invention can be found in United States Patent Class 33, Subclasses 418 through 426, particularly subclasses 418, 419 and 424 through 426.
Innumerable patents have been issued on geometrical instruments, particularly those intended to aid in the layout of construction and building materials such as lumber, metal or steel. Most of these prior art patents deal with squares, protractors, combination squares and the like.
Special tools to deal with pipe and other cylindrical surfaces are fairly common. Yavicoli, U.S. Pat. No. 1,893,973, discloses a squaring tool with two protruding arms at a 45.degree. angle. A ruler used in conjunction with this device is used to mark lines or cords across cylindrical objects. Howard, U.S. Pat. No. 4,914,825 is one of many patented pipe fitting related squaring tools. This patent is typical of such tools. This particular tool employs two 45.degree. arms.
Specially designed tools are also common in the art. Bear, U.S. Pat. No. 5,349,758 discloses a multi-use wood-working square. This device has a pivot point which can be centered or located against the edge of wood to assist in drawing circles or arcs. McCormick, U.S. Pat. No. 981,867, discloses something akin to a "speed" square with a pair of pivoted blades pivoted to the top corner of the square.
Various types of combination squares and modifications to combination squares are present in the art as well. Evans, U.S. Pat. No. 389,370, discloses a bevel square which has a set of fixed angles, particularly 45.degree.. Rakauskas, U.S. Pat. No. 5,276,973, discloses a combination square which has been modified with a second slider to serve as a height and/or width gage. A combination square with a centering head is disclosed in Rowell, U.S. Pat. No. 535,223.
Various folding rules and the like are disclosed in the following patents. Van Gale, U.S. Pat. No. 1,630,773 discloses a folding rule adapted to be used as a set of dividers and/or a compass. Phillips, U.S. Pat. No. 263,351 discloses a yardstick which folds out to a predetermined angle for marking fabric "on the bias".
A protractor with a squaring base and pivoting blade is disclosed in Gilcrest, U.S. Pat. No. 591,964. Will, U.S. Pat. No. 1,613,776, discloses a protractor type device with a squaring base. Elder, U.S. Pat. No. 1,773,809 discloses a protractor which has a straightedge extending therefrom for laying out and/or plotting various line configurations. Liu, U.S. Pat. No. 4,535,542, discloses a 360.degree. protractor with a vernier scale and a pair of sliding straightedges.
Modifications to T-squares to allow them to produce angled lines are quite common. Bronson, U.S. Pat. No. 58,056, discloses a T-square with a protractor head having a pivoting squaring base associated with the protractor. Salot, U.S. Pat. No. 227,844, discloses a T-square having a protractor deployed in combination with the T-square head. Davis, U.S. Pat. No. 1,381,808, discloses an T-square with a pivoting blade, indexing holes at particular angles and a protractor scale across the top of the base. Morris, U.S. Pat. No. 2,423,786, discloses a drafting tool which has a T-square component with a protractor superimposed over the base and a second straightedge pivoted in conjunction with the protractor portion of the device. Dillemuth, U.S. Pat. No. 3,103,749 discloses a square having a head somewhat similar to the frame body of a conventional level with a gear tooth appendage extending therefrom. The appendage can be deployed at various angles.
Multiple straightedges, protractors and the like are combined together to create angle drawing tools in several patents. Terenzoni, U.S. Pat. No. 5,446,969 discloses a square which has a longitudinal slot along one leg of a somewhat conventional framing square. The framing square has a flat, perpendicular edge for helping to square the device. Hopfer, U.S. Pat. No. 4,697,351 discloses a layout square employing a combination square type device and two other locking sliding mechanisms to facilitate drawing angled lines and/or parallel lines or lines parallel to an edge. Some angle drawing tools are extremely complicated. Rohde, U.S. Pat. No. 4,352,247, and Milla, U.S. Pat. No. 1,999,105, disclose rather elaborate square, angle and protractor setups for drawing angled and parallel lines.
Modifications to framing squares and bevels to facilitate drawing angled lines are also common. Hurt, U.S. Pat. No. 4,348,815, and Baumunk, U.S. Pat. No. 2,775,037, disclose adjustable squares with indexing pins for particular angles. Hill, U.S. Pat. No. 304,196, discloses a bevel with a spring loaded detent blade lock. Clark, U.S. Pat. No. 899,692; and Rizianu, U.S. Pat. No. 1,916,638; disclose reinforced bevels with angle indicia on one or both blades. Several Patents including Moore, U.S. Pat. No. 596,818; Hill, U.S. Pat. No. 3,345; Siggson, U.S. Pat. No. 2,656,609; and Dvorak, U.S. Pat. No. 1,210,370; disclose elaborate bevels employing sets of level bubble tubes. Welch, U.S. Pat. No. 4,955,141, discloses an adjustable pivot square somewhat similar to a reinforced or stabilized level.
Schaller, U.S. Pat. No. 714,404, discloses a T-square type device. King (Edward), U.S. Pat. No. 1,525,813, teaches the use of an orifice at each end of a combination square's straightedge to allow the straightedge to pivot about the square's base. Andrews, U.S. Pat. No. 3,510,950, discloses a combination square which employs pins to dispose the straightedge at different fixed angles. Two patents issued to Calvin King, U.S. Pat. Nos., 4,736,524 and 3,828,436, disclose devices employing a squaring head which has a protractor deployed in conjunction with the head and a straightedge extending from the protractor. The later patent, U.S. Pat. No. 4,736,524, uses a vernier type scaled for angle matching. A carpenters square and protractor is disclosed in Wright, U.S. Pat. No. 4,599,806. This device is basically a combination T-square, similar to a draftsman's T-square and protractor. The T-square employs a rotating blade which can be placed at a desired angle. Miller, U.S. Pat. No. 4,702,012, discloses a multi-part tool having a head with a squaring face and fixed positions for a sliding rule at 90.degree. and 45.degree. to either side. The device also mounts a tape measure.
Hence, it is desirous to provide a simple to use Multifunction Layout Tool capable of carrying out the functions of several conventional layout tools in a single unit. Additionally, such a tool should be relatively compact and sturdy to standup to the practical requirements of the work place whether it be a shop, worksite or around the home.